Using ART, what is the risk of having low-birth–weight infants?
Low-birth–weight infants (less than 2,500 grams, or 5 pounds, 9 ounces) are at increased risk for death and short- and long-term disabilities such as cerebral palsy, mental retardation, and limitations in motor and cognitive skills. Figure 12 presents percentages of low-birth–weight infants resulting from ART cycles that used fresh nondonor eggs or embryos, by number of infants born. For singletons, it shows separately the percentages of low birth weight among infants born from pregnancies that started with one fetus (single-fetus pregnancies) and with more than one fetus (multiple-fetus pregnancies). Among singletons born through ART, the percentage of low-birth–weight infants was higher for those from multiple-fetus pregnancies (17%) than those from single-fetus pregnancies (8%). In the general U.S. population, where singletons are almost always the result of a single-fetus pregnancy, 8% of infants born in 2005 (most recent available data) had low birth weights. Approximately 57% of
